179951319X     

Toward a more complete optical census of active galactic nuclei via spatially resolved spectroscopy / Julia M. Comerford, James Negus, R. Scott Barrows, Dominika Wylezalek, Jenny E. Greene, Francisco Müller-Sánchez, and Rebecca Nevin

Comerford, Julia M. [Verfasserin/Verfasser]

Negus, James [Verfasserin/Verfasser] ; Barrows, R. Scott [Verfasserin/Verfasser] ; Wylezalek, Dominika, 1988- [Verfasserin/Verfasser] ; Greene, Jenny E. [Verfasserin/Verfasser] ; Müller Sánchez, Francisco, 1978- [Verfasserin/Verfasser] ; Nevin, Rebecca [Verfasserin/Verfasser]

The astrophysical journal : an international review of spectroscopy and astronomical physics . - London : Institute of Physics Publ. ; Chicago, Ill. [u.a.] : Univ. of Chicago Press, [1995?]-. - Bd. 927 (2022), 1, S. 1-15 = 15 S.

Englisch

Gesehen am 21.04.2022

Elektronische Ressource: Zugang beim Produzenten (Lizenzangabe: Lizenzpflichtig)

Digital Object Identifier (DOI): 10.3847/1538-4357/ac496a

While emission line flux ratio diagnostics are the most common technique for identifying active galactic nuclei (AGNs) in optical spectra, applying this approach to single-fiber spectra of galaxies can omit entire subpopulations of AGNs. Here, we use spatially resolved spectroscopy from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey to construct a sample of 10 galaxies where Baldwin-Philips-Terlevich line flux ratio diagnostics classify each galaxy’s central 3″ spectrum as LINER or star-forming, while >10% of the spaxels in the galaxy’s MaNGA footprint are classified as Seyfert. We obtain Chandra observations of these 10 galaxies with off-nuclear Seyfert regions to determine whether AGNs are actually present in them. Our main result is that 7-10 (depending on strictness of criteria) of the galaxies host one or more X-ray AGNs, even though none of them were classified as AGNs based on their single-fiber optical spectra. We find that these AGNs were not identified in the single-fiber spectra because they are AGNs in the nuclei of companion galaxies, low-luminosity AGNs, dust-obscured AGNs, and/or flickering AGNs. In summary, we find that off-nuclear AGN signatures may increase the number of known AGNs by a factor of two over what conventional single nuclear fiber spectra identify. Our results show that spatially resolved spectroscopy can be leveraged to reveal a more complete census of AGNs that are traditionally missed by single-fiber spectra.